Synthesis of the molecular amalgam [{AuHg2(o-C6F4)3}{Hg3(o-C6F4)3}]−: a rare example of a heterometallic homoleptic metallacycle.

The preparation of homoleptic heterometallic complexes still remains a challenge. Herein, we report the synthesis and characterization of [Au(PMe3)2][{AuHg2(o-C6F4)3}{Hg3(o-C6F4)3}] (1), a gold–mercury homoleptic metallacycle. The crystal structure of 1 displays two [Hg2M(o-C6F4)3] (M = AuI, HgII) units linked through a short Au…Hg contact of 3.097(2) Å, the strongest unsupported AuI…HgII interaction described to date. Theoretical calculations quantify the interaction between the trimetalic units as −199 kJ mol−1, a surprisingly strong value. [ABSTRACT FROM AUTHOR]